Dispersion strengthening in vanadium microalloyed steels processed by simulated thin slab casting and direct charging Part 1 – Processing parameters, mechanical properties and microstructure

Abstract

This version is available at https://strathprints.strath.ac.uk/5778/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the Strathprints administrator: strathprints@strath.ac.ukThe Strathprints institutional repository (https://strathprints.strath.ac.uk) is a digital archive of University of Strathclyde research outputs. It has been developed to disseminate open access research outputs, expose data about those outputs, and enable the management and persistent access to Strathclyde's intellectual output.

Processes, microstructure and properties of vanadium microalloyed steels

“…In fact, the work showed that sub-15 nm particles were nitrogen rich carbonitrides which do not appear to coarsen during the final stages of processing. 154,[175][176][177][178] The carbon extraction replica technique has the advantage of giving good contrast for extracted particles, low background for analysis using PEELS and EDX spectroscopy, and no perturbation of the optical properties of the objective lens from the ferromagnetic material in a typical foil specimen. However, there is some uncertainty about the extraction efficiency for the smallest particles, as very few were found with sizes ,4 nm.…”

“…A similar effect was found in a study of TSDC 0?06 wt-%C steels where, following reheating at 1050uC, despite the smaller ferrite grain size of an 0?1V-0?010Ti-0?017N (wt-%) steel, a reduction in yield strength of 84 MPa was recorded compared with an 0?1V-0?02N (wt-%) steel. 154 With a 0?1V-0?03Nb-0?007Ti (wt-%) steel, the reduction in yield strength was 70 MPa. 154 The comparison of V and V-Nb steels usually shows that an addition of about 0?03-0?04 wt-%Nb results in a gain in yield strength but a loss in toughness.…”

“…154 With a 0?1V-0?03Nb-0?007Ti (wt-%) steel, the reduction in yield strength was 70 MPa. 154 The comparison of V and V-Nb steels usually shows that an addition of about 0?03-0?04 wt-%Nb results in a gain in yield strength but a loss in toughness. No improvement in strength was found in increasing the Nb content to 0?08 wt-% in accelerated cooled steels.…”

“…155 This decrease in dispersion strengthening also occurred in Ti-Nb-V-N steels. 154 A series of papers [156][157][158][159] have compared in detail the precipitate morphologies and compositions of steels containing y0?09C-0?017Ti-0?016Nb-0?044V (wt-%) with y0?07C-0?044V (wt-%) steels. Unfortunately, the N and Si levels were not given.…”

“…A more recent study by Mohamed, 187 who provided a useful succinct review of the literature, 14 ChemSage predictions for a steel V-N, b steel V-NbTi and c volume fractions of dispersion strengthening particles in TSDR processed steels, as function of equalisation temperature 176 15 Experimentally determined size distribution for small particles of V(C,N) (Ref. 154) compared the hot ductility of a Nb steel with a series of steels containing 0?009 to 0?10 wt-%V, all having approximately 0?12 wt-%C and 0?005 wt-%N. The curves generated in this work are given in Fig.…”